I did manage to get hold of a "vintage" Windows Vista ReadyBoost(tm) Module (same thing, with a silly name)... but even that was significantly more expensive!

There isn't anything complicated here, but some tips if you're doing this:

Get the pinouts the right way around (it's mirrored)

Insulate the reverse of the PCB (the header has *two* ports). Kapton tape works well.

Solder the the NC pin to something - just to strengthen the connector

Melt a bit of plastic into the NC hole on the connector

If you use this exact same drive - there's 1 tiny plastic tab you'll need to snap off, and the "connector hole" needs (carefully!) making about 0.5mm wider for it to all fit back together. I opted for widening the casing, and filing the connector top+bottom; for a neater finish.

Here's some pictures:

These are annoying to dismantle without damaging the plastics

The "Vista" module I bought

If you're careful, you can save the USB connector for a future project. I was not:

Hey, it works too!

"In use"

The finished mod, and a side-by-side comparison with the one I bought: